The goal of this core facility is to provide support to various projects of this Program Project in performing tissue culture experiments in collaboration with other investigators in order to achieve the goals of the various projects as outlined in their Specific Aims. In collaboration with Dr. Arlinghaus we will improve the infection of Ph+ CML marrow cells with Ad5BCR. We will first utilize low-density marrow cells and at a later stage we will perform the same experiments with CD34+ cells. Bone marrow cells of hematologically normal individuals, chronic myelogenous leukemia (CML) at the chronic phase, and of CML patients in blastic transformation will be infected and cultured in clonogenic assays. The various clonogenic assays will be used to determine the ability of Bcr peptide to inhibit the growth of Ph+ colony-forming cells. In collaboration with Dr. Claxton we will study cells from patients who will be enrolled on protocol DM96-169. Using co-culture and clonogenic assays, we will test accessory cell anti-CML cytotoxicity following IL-2 therapy. These studies will be performed at different time points of treatment. Together with Dr. Andreeff we will study rare sub-populations of early hematopoietic progenitors in an effort to identify, isolate and grow Ph-negative hematopoietic progenitors from marrow cells of Ph+ CML patients.